U.S. patent application number 12/969616 was filed with the patent office on 2011-06-23 for method for extracting probability model value from probability model table and method and apparatus for decoding symbol value by using the same.
This patent application is currently assigned to ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE. Invention is credited to Min Seok CHOI, Nak Woong Eum, Seong Mo Park.
Application Number | 20110153334 12/969616 |
Document ID | / |
Family ID | 44152347 |
Filed Date | 2011-06-23 |
United States Patent
Application |
20110153334 |
Kind Code |
A1 |
CHOI; Min Seok ; et
al. |
June 23, 2011 |
METHOD FOR EXTRACTING PROBABILITY MODEL VALUE FROM PROBABILITY
MODEL TABLE AND METHOD AND APPARATUS FOR DECODING SYMBOL VALUE BY
USING THE SAME
Abstract
A method for extracting a probability model value from a
probability model table and a method and apparatus for decoding a
symbol value using the same are provided. The method for extracting
a probability model value from a probability model table includes:
segmenting and reducing a probability model table including a
plurality of probability model values; disposing indexes on the
basis of the segmented and reduced probability model table; and
searching the probability model table for a probability model value
by using the disposed indexes.
Inventors: |
CHOI; Min Seok; (Daejeon,
KR) ; Park; Seong Mo; (Daejeon, KR) ; Eum; Nak
Woong; (Daejeon, KR) |
Assignee: |
ELECTRONICS AND TELECOMMUNICATIONS
RESEARCH INSTITUTE
Daejeon
KR
|
Family ID: |
44152347 |
Appl. No.: |
12/969616 |
Filed: |
December 16, 2010 |
Current U.S.
Class: |
704/500 ;
704/E19.001 |
Current CPC
Class: |
H04N 21/4382 20130101;
H03M 7/4006 20130101; G10L 19/24 20130101 |
Class at
Publication: |
704/500 ;
704/E19.001 |
International
Class: |
G10L 19/00 20060101
G10L019/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 18, 2009 |
KR |
10-2009-0127515 |
Nov 22, 2010 |
KR |
10-2010-0116262 |
Claims
1. A method for extracting a probability model value from a
probability model table, the method comprising: segmenting and
reducing a probability model table including a plurality of
probability model values; disposing indexes on the basis of the
segmented and reduced probability model table; and searching the
probability model table for a probability model value by using the
disposed indexes.
2. The method of claim 1, wherein the disposing of the indexes on
the basis of the segmented and reduced probability model table
removes an unnecessary index searching process.
3. A method for decoding a symbol value using a method for
extracting a probability model value from a probability model
table, the method comprising: receiving a symbol value to be
decoded; extracting a probability model value from a probability
model table; and decoding the received symbol value by using the
extracted probability model value.
4. The method of claim 3, wherein the extracting of the probability
model value from the probability model table comprises: segmenting
and reducing the probability model table including a plurality of
probability model values; disposing indexes on the basis of the
segmented and reduced probability model table; and searching the
probability model table for a probability model value by using the
disposed indexes.
5. The method of claim 4, wherein the disposing of the indexes on
the basis of the segmented and reduced probability model table
removes an unnecessary index searching process.
6. The method of claim 3, wherein the symbol value decoding method
is used for BSAC (Bit Sliced Arithmetic Coding) decoding, an audio
coding standard of terrestrial DMB (Digital Multimedia
Broadcasting).
7. An apparatus for decoding a symbol value by using a method for
extracting a probability model value from a probability model
table, the apparatus comprising: a memory storing a probability
model table including a plurality of probability model values; and
a processor receiving a symbol value to be decoded, extracting a
probability model value from the probability model table stored in
the memory, and decoding the received symbol value.
8. The apparatus of claim 7, wherein when the processor extracts
the probability model value from the probability model table, it
segments and reduces the probability model table including a
plurality of probability model values, disposes of indexes on the
basis of the segmented and reduced probability model table, and
searches the probability model table for a probability model
value.
9. The apparatus of claim 7, wherein the symbol value decoding
apparatus is used for BSAC (Bit Sliced Arithmetic Coding) decoding,
an audio coding standard of terrestrial DMB (Digital Multimedia
Broadcasting).
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority of Korean Patent
Application No. 10-2009-0127515 filed on Dec. 18, 2009 and Korean
Patent Application No. 10-2010-0116262 filed on Nov. 22, 2010, in
the Korean Intellectual Property Office, the disclosure of which is
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a method for extracting a
probability model value from a probability model table and a method
and apparatus for decoding a symbol value using the same, and more
particularly, to a method for extracting a probability model value
from a probability model table having a reduced amount of
calculation and a method and apparatus for decoding a symbol value
using the same.
[0004] 2. Description of the Related Art
[0005] Recently, as a DMB (Digital Multimedia Broadcasting)
reception terminal has been rapidly spreading and has become
generalized, users can enjoy a high quality multimedia service
through a personal mobile device such as a vehicle terminal, a
mobile phone, a PDA, or the like, in a mobile reception
environment.
[0006] An ISO/IEC 14496-3 BSAC (Bit Sliced Arithmetic Coding)
standard has been adopted as an audio coding scheme in a Korean
standard for DMB service, in particular, terrestrial DMB service.
The BSAC is one of a natural audio coding methods of MPEG-4, and
its basic signal processing techniques for compression are the same
as those of MPEG-4 AAC (Advanced Audio Coding), a typical high
sound quality audio coding method; however, the BSAC is different
from the MPEG-4 AAC in that it uses arithmetic coding, instead of
Huffman coding, as a lossless coding method.
[0007] An arithmetic decoding process in a BSAC audio decoding
process is used to restore an MDCT (Modified Discrete Cosine
Transform) coefficient from a coded MPEG-4 BSAC bit stream, which
is sequentially performed from a lower layer to a higher layer by
scalability layer.
[0008] The arithmetic decoding process, however, requires a great
amount of calculation in the process of finding a probability model
value of each bit with respect to each symbol, having difficulty in
being implemented in a universal DSP (Digital Signal Processor), or
the like.
[0009] Thus, a method of implementing the process of finding a
probability model value in the arithmetic decoding process by using
dedicated hardware, a method of reducing a search range by
segmenting a probability model table, or the like, has been
proposed.
[0010] In this case, however, there is a burden of additionally
developing dedicated accelerating hardware for the arithmetic
decoding process, and a major calculation in the arithmetic
decoding process arises from the condition of searching an index
with respect to the probability model table and a branching
process, so the method for fragmenting the probability model table
cannot achieve the effect of greatly reducing the amount of
required calculation.
SUMMARY OF THE INVENTION
[0011] An aspect of the present invention provides a method for
extracting a probability model value from a probability model
table.
[0012] Another aspect of the present invention provides a method
for decoding a symbol value using a method for extracting a
probability model value from a probability model table.
[0013] Another aspect of the present invention provides an
apparatus for decoding a symbol value using a method for extracting
a probability model value from a probability model table.
[0014] According to an aspect of the present invention, there is
provided a method for extracting a probability model value from a
probability model table, including: segmenting and reducing a
probability model table including a plurality of probability model
values; disposing indexes on the basis of the segmented and reduced
probability model table; and searching the probability model table
for a probability model value by using the disposed indexes.
[0015] The disposing of the indexes on the basis of the segmented
and reduced probability model table may remove an unnecessary index
searching process.
[0016] According to an aspect of the present invention, there is
provided a method for decoding a symbol value using a method for
extracting a probability model value from a probability model
table, including: receiving a symbol value to be decoded;
extracting a probability model value from a probability model
table; and decoding the received symbol value by using the
extracted probability model value.
[0017] The extracting of the probability model value from the
probability model table may include: segmenting and reducing the
probability model table including a plurality of probability model
values; disposing indexes on the basis of the segmented and reduced
probability model table; and searching the probability model table
for a probability model value by using the disposed indexes.
[0018] The disposing of the indexes on the basis of the segmented
and reduced probability model table may remove an unnecessary index
searching process.
[0019] The symbol value decoding method may be used for BSAC (Bit
Sliced Arithmetic Coding) decoding, an audio coding standard of
terrestrial DMB (Digital Multimedia Broadcasting).
[0020] According to an aspect of the present invention, there is
provided an apparatus for decoding a symbol value by using a method
for extracting a probability model value from a probability model
table, including: a memory storing a probability model table
including a plurality of probability model values; and a processor
receiving a symbol value to be decoded, extracting a probability
model value from the probability model table stored in the memory,
and decoding the received symbol value.
[0021] When the processor extracts the probability model value from
the probability model table, it may segment and reduce the
probability model table including a plurality of probability model
values, dispose of indexes on the basis of the segmented and
reduced probability model table, and search the probability model
table for a probability model value.
[0022] The symbol value decoding apparatus may be used for BSAC
(Bit Sliced Arithmetic Coding) decoding, an audio coding standard
of terrestrial DMB (Digital Multimedia Broadcasting).
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The above and other aspects, features and other advantages
of the present invention will be more clearly understood from the
following detailed description taken in conjunction with the
accompanying drawings, in which:
[0024] FIG. 1 is a flow chart illustrating the process of a method
for extracting a probability model value from a probability model
table according to an exemplary embodiment of the present
invention;
[0025] FIGS. 2 and 3 are views illustrating a method for extracting
a probability model value from a probability model table according
to the related art;
[0026] FIGS. 4 and 5 are views illustrating a method for extracting
a probability model value from a probability model table according
to an exemplary embodiment of the present invention;
[0027] FIG. 6 is a flow chart illustrating the process of a method
for decoding a symbol value by using a method for extracting a
probability model value from a probability model table according to
an exemplary embodiment of the present invention; and
[0028] FIG. 7 is a schematic block diagram of an apparatus for
decoding a symbol value by using a method for extracting a
probability model value from a probability model table according to
an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] The present invention may be modified variably and may have
various embodiments, particular examples of which will be
illustrated in drawings and described in detail.
[0030] However, it should be understood that the following
exemplifying description of the invention is not intended to
restrict the invention to specific forms of the present invention
but rather the present invention is meant to cover all
modifications, similarities and alternatives which are included in
the spirit and scope of the present invention.
[0031] While terms such as "first" and "second," etc., may be used
to describe various components, such components must not be
understood as being limited to the above terms. The above terms are
used only to distinguish one component from another. For example, a
first component may be referred to as a second component without
departing from the scope of rights of the present invention, and
likewise a second component may be referred to as a first
component. The term "and/or" encompasses both combinations of the
plurality of related items disclosed and any item from among the
plurality of related items disclosed.
[0032] Unless otherwise defined, all terms used herein, including
technical or scientific terms, have the same meanings as those
generally understood by those with ordinary knowledge in the field
of art to which the present invention belongs. Such terms as those
defined in a generally used dictionary are to be interpreted as
having meanings equal to the contextual meanings in the relevant
field of art, and are not to be interpreted as having ideal or
excessively formal meanings unless clearly defined as having such
in the present application.
[0033] Embodiments of the present invention will be described below
in detail with reference to the accompanying drawings, where those
components are rendered using the same reference number that are
the same or are in correspondence, regardless of the figure number,
and redundant explanations are omitted.
[0034] FIG. 1 is a flow chart illustrating the process of a method
for extracting a probability model value from a probability model
table according to an exemplary embodiment of the present
invention.
[0035] With reference to FIG. 1, a method for extracting a
probability model value from a probability model table according to
an exemplary embodiment of the present invention includes: a step
(110) of segmenting and reducing a probability model table
including a plurality of probability model values; a step (120) of
disposing indexes on the basis of the segmented and reduced
probability model table; and a step (130) of searching the
probability model table for a probability model value by using the
disposed indexes.
[0036] First, in the step (110) of segmenting and reducing the
probability model table including the plurality of probability
model values, the respective probability model values of the
probability model table may be segmented and a reducible item may
be reduced.
[0037] Next, in the step (120) of disposing the indexes on the
basis of the segmented and reduced probability model table, an
unnecessary index may be removed from the indexes to allow the
segmented and reduced probability model table to be well shown.
[0038] Also, in the step (120) of disposing the indexes on the
basis of the segmented and reduced probability model table, an
unnecessary index searching process may be eliminated.
[0039] In the step (130) of searching the probability model table
for a probability model value by using the disposed indexes, the
probability model table may be searched for a probability model
value and the searched probability model value may be
extracted.
[0040] Namely, the probability model value may be searched and
extracted so as to be used for a decoding operation.
[0041] FIGS. 2 and 3 are views illustrating a method for extracting
a probability model value from a probability model table according
to the related art.
[0042] With reference to FIGS. 2 and 3, in the method for
extracting a probability model value from a probability model table
according to the related art, as shown in FIG. 2, a probability
model index may be searched from a probability model table
cband_si_cbook tbl[] as shown in FIG. 3 according to
cband_si_type[ch] value transmitted from a transmission end, and
then coding band supplementary information model_index[ch][cband]
may be arithmetically decoded from a probability value table
corresponding to a pertinent index from a probability value table
AModelCBand[ ][ ].
[0043] Here, ch refers to each channel of stereo channels, and
cband refers to a coding band (frequency band) to which an
arithmetic coding is applied.
[0044] As shown in FIG. 3, it is noted that the probability value
tables of the respective probability models have different lengths
and include unnecessary probability values. Thus, the probability
value tables illustrated in FIG. 3 may be separated by probability
models and those which have been allocated with unnecessary
probability values may be eliminated. This means that memory space
unnecessarily used for storing probability value tables may be
saved.
[0045] FIGS. 4 and 5 are views illustrating a method for extracting
a probability model value from a probability model table according
to an exemplary embodiment of the present invention.
[0046] With reference to FIGS. 4 and 5, in the method for
extracting a probability model value from a probability model table
according to an exemplary embodiment of the present invention.
Specifically, FIG. 4 shows a pseudo-code for a process of
arithmetically decoding coding band supplementary information
proposed by the present invention, and FIG. 5 shows a segmented and
reduced probability value table for arithmetically decoding coding
band supplementary information.
[0047] As shown in FIG. 4, the coding band supplementary
information model_index[ch][cband] can be arithmetically decoded by
using the probability value table AModelCBand# in FIG. 5 according
to the value cband_si_type[ch] with respect to a current channel
transmitted from a transmission end.
[0048] As a result, the process of obtaining a probability model
table in the arithmetic decoding process and obtaining the index of
the probability model table, which accounts for 60% or more of the
entire amount of calculation of the audio decoding apparatus, can
be simplified.
[0049] FIG. 6 is a flow chart illustrating the process of a method
for decoding a symbol value by using a method for extracting a
probability model value from a probability model table according to
an exemplary embodiment of the present invention.
[0050] With reference to FIG. 6, a method for decoding a symbol
value using a method for extracting a probability model value from
a probability model table according to an exemplary embodiment of
the present invention includes: a step (610) of receiving a symbol
value to be decoded; a step (620) of extracting a probability model
value from a probability model table; and a step (630) of decoding
the received symbol value by using the extracted probability model
value.
[0051] First, in the step (610) of receiving a symbol value to be
decoded, a symbol value, to which a decoding method according to an
exemplary embodiment of the present invention is to be applied, may
be received.
[0052] Next, the step (620) of extracting the probability model
value from the probability model table may include: segmenting and
reducing the probability model table including a plurality of
probability model values; disposing indexes on the basis of the
segmented and reduced probability model table; and searching the
probability model table for a probability model value by using the
disposed indexes.
[0053] In addition, the disposing of the indexes on the basis of
the segmented and reduced probability model table may be
eliminating an unnecessary index searching process.
[0054] Thereafter, in the step (630) of decoding a symbol value,
decoding may be performed by using the extracted probability model
value. As a result, decoding is performed on the symbol value
provided in step 610 by using the probability model value extracted
in step 620.
[0055] Meanwhile, the symbol value decoding method may be used for
BSAC (Bit Sliced Arithmetic Coding) decoding, an audio coding
standard of terrestrial DMB (Digital Multimedia Broadcasting).
[0056] FIG. 7 is a schematic block diagram of an apparatus for
decoding a symbol value by using a method for extracting a
probability model value from a probability model table according to
an exemplary embodiment of the present invention.
[0057] With reference to FIG. 7, the apparatus for decoding a
symbol value by using a method for extracting a probability model
value from a probability model table according to an exemplary
embodiment of the present invention may include: a memory 710
storing a probability model table including a plurality of
probability model values; and a processor 720 receiving a symbol
value to be decoded, extracting a probability model value from the
probability model table stored in the memory, and decoding the
received symbol value.
[0058] Here, when the processor extracts the probability model
value from the probability model table, it may segment and reduce
the probability model table including a plurality of probability
model values, dispose of indexes on the basis of the segmented and
reduced probability model table, and search the probability model
table for a probability model value.
[0059] In addition, the symbol value decoding apparatus may be used
for BSAC (Bit Sliced Arithmetic Coding) decoding, an audio coding
standard of terrestrial DMB (Digital Multimedia Broadcasting).
[0060] As set forth above, in the method for extracting a
probability model value from a probability model table and the
method and apparatus for decoding a symbol value using the same
according to exemplary embodiments of the invention, the process of
obtaining a probability model table of an arithmetic decoding
process and obtaining an index of the probability model table,
accounting for 60% or more of the entire amount of calculation of
an audio decoding apparatus, can be simplified. In particular,
because the process of obtaining the probability model table of the
arithmetic decoding process and obtaining the index of the
probability model table is simplified, a required amount of memory
and calculation can be reduced, thus facilitating an implementation
using a universal DSP, or the like.
[0061] While the present invention has been shown and described in
connection with the exemplary embodiments, it will be apparent to
those skilled in the art that modifications and variations can be
made without departing from the spirit and scope of the invention
as defined by the appended claims.
* * * * *